The present invention relates to a method and system for the thermal analysis of a substance. Lasers play an important role in the thermal analysis, lending to its accuracy and expediency. The method and system of the present invention can be used in many technical applications, e.g., the destruction of hazardous waste material.
Methods and systems for the thermal analysis of various materials are well known in the art. For example, see U.S. Pat. No. 3,847,546 which discloses a temperature programmed solid sample chamber. The chamber is adapted to apply thermal energy to a sample material. The carrier gases flow through the chamber whose temperature is raised at a programmed, relatively slow rate to limit the thermal energy applied to the sample. The effluent gases containing the decomposition products are swept through a first detector and then through a first valve to a vent. After storage, the effluent gases are then passed through a second detector. The information obtained from the two detectors is used to analyze the particular substance under investigation.
The accuracy and reproducibility of the information obtained has often been a problem with prior art thermal analysis techniques. When wanting to study the actual chemical/physical process a substance undergoes during thermal degradation, the prior art analyses have also been quite deficient in their ability to accurately obtain data which can be used in an appropriate analysis.
The rate of the energy exchange during chemical/physical processes is usually measured in a reactor. It is determined either from the rate of change of sample weight, or by measurement of the thermal currents from the sample caused by heat evolution or absorption during this process. For a number of chemical/physical processes (thermal destruction, incineration, evaporation and phase transfer) the important property of the reactor is the rate of change of the temperature therein. If the reactor temperature rises slowly, the chemical process can finish before the temperature region of interest is reached. Accordingly, for rapid sample heating, the present inventor developed a laser device and a laser control device as described in the U.S.S.R. Certificate of Invention S.U. No. 124117, which is hereby incorporated by reference. The reactor permits one to achieve more efficient and accurate measurements, thereby expanding its potential practical applicability.
Indeed, increasing attention is being paid to the treatment of hazardous waste through thermal destruction. Among the preferred technologies are thermal processes that de-toxify and reduce the volume of hazardous wastes by exposing them to appropriate thermal regimes. However, as with any technology, there are potential problems which may detract from the application of the technology. Environmental pollution from particulate matter and off-gases can occur. Therefore, if practical, efficient and accurate, a suitable thermal analysis system and method could play a very important role in the development of hazardous waste treatment technology by permitting one to determine the parameters and conditions of appropriate thermal processes.
The laser used in such a thermal reactor can also be monitored and controlled by an intensity control system to aid in the uniformity of the heating of the sample substance, and hence improving the accuracy and usefulness of the information subsequently obtained. Such laser intensity and control systems are well known. For example, see U.S. Pat. No. 4,122,409; U.S. Pat. No. 4,504,951; as well as the inventor's own U.S.S.R. Certificate of Invention S.U. No. 1,597,068, which is hereby incorporated by reference.
Yet, the application of such methods and systems to many technical fields still requires an improvement in the measurement techniques, the accuracy of the information obtained and the usefulness of the information obtained, for the application to be of practical significance. Technical applications such as the treatment of waste materials would dearly welcome the existence of a practical and useful thermal analysis method and system.
Accordingly, it is an object of the present invention to provide a novel and improved method for the thermal analysis of a substance, such as waste material, liquid fuels, coal and others.
Yet another object of the present invention is to provide a novel system for use in said method of thermal analysis.
Yet another object of the present invention is to provide a method and system for the thermal analysis of a sample substance which would be readily applicable for many technical processes, and in particular waste treatment.
These and other objects of the present invention will become apparent upon a review of the following specification, the Figures of the Drawing, and the claims appended thereto.